Heat interchange device



Patented July 16, 1935 UNITED STATES HEAT INTERCHAN GE DEVICE Francesco B. Whittemor William J. Perkins, B

e, Jackson Heights, and rooklyn, N. Y., assignors to International Motor Company, New York,

N. Y., a corporation of Application February 18 Delaware 1933, Serial No. 657,368

aclaims. (01. 62-102) The present invention relates to refrigerating mechanism and embodies, more specifically, an improved refrigerating mechanism for motor vehicles wherein means is provided for preserv- 6 ing a predetermined humidity within the space to be refrigerated.

In refrigerating certain products, it is necessary to preserve a predetermined humidity about the products to prevent deterioration and spoilage thereof. For example, certain food products, such as eggs, green fruit and vegetables particularly of the leafy type require relatively high humidity and certain of these commodities are aflected by even a comparatively short exposure to an atmosphere of low humidity. In ref rigerating mechanisms now available, no attention has been given to the question of humidity and these mechanisms are therefore not suitable for the storage and transportation of products requiring high humidity. This is particularly true of mechanisms utilizing solid'carbon dioxide asa refrigerant in as much as the large temperature difference between the atmosphere within the refrigerating compartment and the temperature of the refrigerating plate or heat transfer element gives rise to a marked dehumidifying action upon the air within the refrigerating compartment.

In order that an effective refrigerating mechanism may be utilized in refrigerating systems of the above character and adapted for use in connection with all commodities, the present invention has been designed and an object thereof is to provide a refrigerating mechanism by means of which a desired humidity may be maintained within a refrigerating compartment.

A further object'of the invention is to provide an improved refrigerating mechanism by means of which effective refrigeration may be accomplished without disturbing the humidity within the refrigerating chamber.

, Further objects, not specifically enumerated above, will be apparent as the invention is described in greater detail in connection with the accompanying drawing, wherein:

Figure 1 is a view in vertical section, taken on line l-l of Figure 2, and looking in the direction of the arrows.

Figure 2 is a plan view, partly broken away and in section, showing the refrigerating mechanism 50 of Figure 1.

Figure 3 is a detail view of a modified form of the invention, the view being in section to illus-= trate the elements of the mechanism.

Figure 4 is a view similar to Figure 3, showing afurther modification of the invention.

With reference to the construction shown in Figures 1 and'2, a refrigerating compartment is illustrated at In having associated therewith a compartment ll within which a refrigerant may be stored, the bottom of the compartment l I comprising a heat transfer plate I2 beneath which heat transfer fins l3 extend downwardly. A longitudinal baflle plate It is provided to control the flow of air beneath the heat transfer plate and the region beneath the bottom plate I2 is closed by a partition [5 which forms a heat transfer compartment l6. Air inlet l1 and outlet I8 is formed in the partition, an outlet pipe I 9 being provided to direct air into the inlet while an outlet pipe 20 is provided to direct air from the out;- let l8 to a circulating fan 2 I. The outlet pipe 20 is formed with a bottom plate 2| which is of good conducting character and which is provided with upwardly, extending fins 22 within the'outlet pipe.

A block of ice, solid carbon dioxide or other refrigerant 23 is placed within the compartment I I through a door 24. The circulating fan 2| causes a circulation of air through the heat interchange compartment l6, thus cooling the air and producing a low temperaturein the air stream directed through the outlet pipe 20. In order that the low temperature of the air within the outlet pipe may be utilized as a refrigerating, medium, the heat exchange plate 2| forming the bottom plate of the outlet pipe 20 also serves as the top of a secondary heat interchange duct 25 which receives air through a duct 26 from the chamber l0. Downwardly extending fins 21 may be formed on the plate 2| to facilitate the interchange of heat between the pipe 20 and the duct 25. The duct 25 communicates with a circulating fan 28, the outlet of which communicates with a pipe 29 which directs the air into the refrigerating compartment in. In this fashion, the temperature drop between the air within the outlet pipe 20 and duct 25 is insufliciently high to eifect a substantial dehydration of the air within the refrigerating chamber. The substantial temperature differential between the cold element I2 and the air within the heat interchange compartment I6 is of no consequence in as much as the dehumidifying of the air within this closed cycle has no effect upon the air which circulates within the refrigerating chamber. By maintaining the air circulating about the primary heat interchange plate in a closed system and separate from the air circulating about the secondary heat interchange plate a substantial temperature difference between the secondary heat interchange element and the air within the refrigerating compartment is avoided and thus the air within the refrigerating compartment is not dehumidified.

In the construction shown in Figure 3, a heat interchange compartment 30 is shown within which a refrigerant compartment3| is provided. The refrigerating medium is placed within the compartment 3| and upon a heat interchange plate 32 beneath which air is circulated by means of a fan 33. This air circulates under a secondary heat interchange element 34 upon which upper and lower fins 35 and 36, respectively, are formed. The region over the plate 34 is closed by a duct 31 through which air is directed in order that the temperature thereof may be controlled. This construction illustrates a simplified form of the invention and is generally similar to the construction shown in Figures 1 and 2.

In the construction shown in Figure 4, a further modified form of the invention is illustrated, this form being of simplified character. A refrigerant compartment 38 is provided within which a suitable refrigerant may be placed. Above the refrigerant, and forming the top of the compartment 38, is a heat interchange plate 39 upon which upwardly and downwardly extending fins 40 and 4|, respectively, are provided. A circulating fan 42 directs air across the flns 4| and over the refrigerant within the compartment 38, a guide plate 43 being provided to preserve a proper flow along the fins 4|. Air is directed over the plate 39 and through a duct 44, this air being circulated between the fins 40 and a suitable refrigerating chamber.

Itwill thus be seen that, by isolating the primary and auxiliary refrigerating circuits, the temperature drop between the secondary refrigerating air which circulates through the refrigerating compartment and the primary air which circulates over the heat interchange elements exposed to the refrigerant is decreased in such fashion that dehumidifying of the secondary air does not take place. The fiow of the air in the primary and secondary circuits may be controlled in any desired fashion, in accordance with existing refrigerating mechanisms.

While the invention has been described with specific reference to the accompanying drawing, it is not to be limited, save as defined in the appended claims.

We claim as our invention:

1. A refrigerating mechanism comprising a refrigerating chamber, a refrigerant chamber, a primary heat interchange element forming a wall of the refrigerant chamber, a closed heat interchange compartment communicating with the primary heat interchange element, a secondary heat interchange element communicating with the last named compartment, and means forming a communication between the secondary element andthe refrigerating chamber.

2. A refrigerating mechanism comprising a refrigerating chamber, a refrigerant chamber, a primary heat interchange element forming a wall of the refrigerant chamber against which a refrigerating means is adapted to engage, a closed heat interchange compartment communicating with the primary heat interchange element, a secondary heat interchange element communicating with the last named compartment, and means forming a communication between the secondary element and the refrigerating chamber.

3. A refrigerating mechanism comprising a chamber, a refrigerating means, a heat interchange element spaced from the refrigerating means and refrigerated thereby, mechanical means to direct fluid and control the flow thereof between the element and the refrigerating means whereby the temperature of the element may be controlled independently of the refrigerating means, and means to direct fluid from the element to the chamber.

4. A refrigerating mechanism comprising a chamber, a refrigerating means, a heat interchange element spaced from the refrigerating means, means to direct fluid and control the flow thereof between the element and the refrigerating means whereby the temperature of the element may be controlled independently of the refrigerating means, and means to direct a separate fluid stream from the element to the chamber.

5. A refrigerating mechanism comprising a chamber, a refrigerating means, a heat interchange element spaced from the refrigerating means, means to direct fluid and control the flow thereof between the element and the refrigerating means in a closed cycle whereby the temperature of the element may be controlled independently of the refrigerating means, and means to direct fluid from the element to the chamber.

6. A refrigerating mechanism comprising a chamber, a refrigerating means, a primary heat interchange means, a secondary heat interchange means controllably communicating with the chamber, and means to control the communication between the secondary heat interchange means and the chamber, the primary and secondary means being independent of each other whereby the temperature of the element may be controlled independently of the refrigerating means.

7. A refrigerating mechanism comprising a refrigerating chamber, a refrigerant chamber, a heat interchange element associated with the refrigerant chamber and spaced from refrigerant therein, means to circulate and control the flow of a fluid between the element and the refrigerant, whereby the temperature of the element may be controlled independently of the refrigerating means, means forming a communication between the element and the refrigerating chamber, and means to circulate a fluid through the last named means.

8. A refrigerating mechanism comprising a refrigerating chamber, a refrigerant chamber, a primary heat interchange element forming the bottom wall of the refrigerant chamber, a closed heat interchange compartment communicating with the primary heat interchange element, a secondary heat interchange element communicating with the last named compartment, and means forming a communication between the secondary element and the refrigerating chamber.

' 9. A refrigerating mechanism comprising a refrigerating chamber, a refrigerant chamber, a

primary heat interchange element forming the bottom wall of the refrigerant chamber, a closed heat interchange compartment communicating with the primary heat interchange element, a secondary heat interchange element communicating with the last named compartment, means forming a communication between the secondary element and the refrigerating chamber, and means to circulate air in the heat interchange compartment and the last named communicating means.

FRANCESCO B. WHITTEMORE. WILLIAM J. PERKINS. 

